A candle that has not been burned is 21 cm tall. After burning for 4 hours at a constant rate, the candle is 11 cm tall. Let h represent the height of the candle in centimeters and t represent the time in hours.

1.
Calculate the hourly rate at which the candle burns. Show your procedure.

2.
Write an equation relating the height, h, of the candle to the number of hours t the candle burns.

3.
Using your equation from question 2, calculate to the nearest hour how long the candle has burned when it is 5 cm tall. Show your work.

c:

Question

A candle that has not been burned is 21 cm tall. After burning for 4 hours at a constant rate, the candle is 11 cm tall. Let h represent the height of the candle in centimeters and t represent the time in hours.

1.	
Calculate the hourly rate at which the candle burns. Show your procedure.

2.	
Write an equation relating the height, h, of the candle to the number of hours t the candle burns.

3.	
Using your equation from question 2, calculate to the nearest hour how long the candle has burned when it is 5 cm tall.  Show your work.


c:

anonymous · Answer

since the total length burned is 10 cm in 4 hrs, what is the amount of candle burned per hour?

anonymous · Answer

That would be 2.5 cm per hour, right?

anonymous · Answer

correct...

anonymous · Answer

using that rate (slope) we can model the height of the candle as it burns for t hours.

anonymous · Answer

let y= the height of the candle at any time, t, we put in.  
at time = 0, what's the height of the candle?

anonymous · Answer

before it is even lit, what is the length of the candle?  this is t=0

anonymous · Answer

It started at 21cm

anonymous · Answer

ok.. so we have this...

anonymous · Answer

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